Of 26 patients with bronchopulmonary dysplasia, 20 (77%) survived and were followed prospectively for two years post-term. Lower respiratory tract infections occurred in 17 of the 20 children (85%), and required hospitalization in ten (50%) during the first and in four (20%) during the second year. At two years post-term only two patients had significant respiratory symptoms at rest, but 78% had residual radiographic changes. The average weight and height at term were at or below the third percentile. Growth occurred at an accelerated rate with improvement of respiratory symptoms, with average weight reaching the third to tenth percentile for both sexes, and tenth to twenty-fifth percentile for height in the boys and the twenty-fifth percentile for the girls by two years post-term. Growth retardation was associated with severe and prolonged respiratory dysfunction. Fifteen (75%) were free of major developmental defects. Five had mean Bayley scores less than 85 at 18 months post-term; one also had hydrocephalus. Developmental outcome seems related to perinatal and neonatal events rather than to the presence or absence of BPD.